 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.ui.internal.keys;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.widgets.Event;
 import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.Widget;

 /**
  * A listener that removes the out-of-order listener if a modification occurs
  * before reaching it. This is a workaround for Bug 53497.
  *
  * @since 3.0
  */
 final class CancelOnModifyListener implements Listener {

     /**
      * The listener to remove when this listener catches any event. This value
      * should not be <code>null</code>.
      */
     private final Listener chainedListener;

     /**
      * Constructs a new instance of <code>CancelOnModifyListener</code>
      *
      * @param listener
      * The listener which should be removed in the event of a
      * modification event arriving; should not be <code>null</code>.
      */
     CancelOnModifyListener(Listener listener) {
         chainedListener = listener;
     }

     /*
      * (non-Javadoc)
      *
      * @see org.eclipse.swt.widgets.Listener#handleEvent(org.eclipse.swt.widgets.Event)
      */
     public void handleEvent(Event event) {
         Widget widget = event.widget;
         widget.removeListener(SWT.Modify, this);
         widget.removeListener(SWT.KeyDown, chainedListener);
     }
 }

